Concrete-grooving device



Sept. 3, 1929. J. w. HELTZEL CONCRETE GROOVING DEVICE Filed March 11. 1926 3 Sheets-Sheet 1 P 1929- J. w. HELTZEL CONCRETE GROQVING DEVI CE Filed March 11, 1926 5 Sheets-Sheet 2 Sept. 3, 1929. w, HELTZEL' 1,726,665

CONCRETE GROOVING DEVICE Filed March 11, 1926 3 Sheets-Sheet 5 inventor:

Patented Sept. 3, 1929.

UNITED STATES PATENT OFFICE.

:rosnrn WILLIAH HELTZEL, or WARREN, onto.

concnn'rn-enoovino DEVICE.

Application filed March 11, .1926. Serial no. 93,977.

The present invention relates to the building of concrete roads or other concrete surfacing structures, and the invention aims to provide a novel means for controlling the breaking or fracturing of the concrete after it has set, and such means may also be used for making traflic lines and joints in concrete roads or other surfacing structures.

As well known, roads and other surfacing structures composed of concrete will crack along irregular lines due to traffic or climatic changes, and a concrete road will usually become fractured along irregular lines has been a difiicult problem to install such division plates along a straight or regular line, and even with the use of such division plates an irregular break occurs, which, however, is not quite as objectionable as a natural break.

With the foregoing objections in view, it

is an object of the present invention to con? i I trol the breaking of the concrete or to make a joint in the concrete whichwill be less expensive and more eflective than the use of division plates as heretofore. With these ends in view, division plates or strips are used which are of less height than the division plates heretofore used, to provide for economy, and to space the upper edges of the division plates or strips several inches below the surfaceof the concrete. These division plates or strips may also be installed more quickly, with a saving in cost, inasmuch as they need not be accurately disposed on the sub-base. This obtains a saving both in material and in installation, and, moreover, the division plates or strips do notinterfere with the tamping or finishing off of the concrete above the division plates, as has occurred with the use (if the ordinary division plates that extend to or adjacent thesu'rface of the concrete. The invention consists further 1n forming a groove in the surface of sitely moving traflic.

the concrete above the division plates or strips. This groove may be formed quickly and accurately, so as to present a regular and accurate line, for purpose of appearance. After the concrete has hardened, it will break between the groove and division plates or strips, said groove weakening the concrete above the division plates or stri s so that the concrete, in cracking, will reak along the line of the groove, which is the line of least resistance in the fracturing of the concrete. In this way, the breaking or fracturingof the concrete is controlled, for producing ajoint in the concrete which may also serve as a traffic line for dividing oppo- A further object of the invention is the provision of a novel device for producing a groove or cut in the plastic concrete.-

With the foregoing and other objects in view, which will be apparent as the invention is more fully understood,the invention resides in the means ashereinafter described and claimed, it being understood that changes may be made within thescope' of what is claimed, without departing from the spirit of the invention.

The invention is illustrated in the accompanying drawings, wherein Figure 1 is a perspective ,view showing the several steps of the method employed and also illustrating the groove formingv device in use.

Fig. 2 is a plan view of said device. Fig; 3 is an elevation of said device illustrating a portion of the road in cross section. Fig. 4 is a perspective view illustrating a modified form of grooving device.

1 Fig. 5 is a perspective view'illustrating a modified form of divdsion plate or strip.

Figs. G and 7 .are cross-sections of completed joints showing modifications in the division plates or strips.

Although the invention is described in connection with the building of a concrete road,

it will be understood that same may be" used for other concrete surfacing structures for which the invention is suitable. When-building a concrete road the side forms or rails 7 are disposed on the ground or sub-base to define the sides or longitudinal edges of the road, and the grout is poured between said rails and the surface of the concrete I,

- per surface of the concrete.

control the longitudinal breaking of the con crete along the center line of the road, division plates or strips 8are placed on the subbase along the line where the longitudinal break is desired. These strips 8 may be of thin sheet metal, so as to be inexpensive, and need only be of a height of two or three inches (more or less), so that their upper edges are spaced several inches below the surface of the concrete in the completed road. Such strips are therefore considerably cheaper than division plates heretofore used which extend from the sub-base to the up- It is unnecessary to locate the strips 8 along the desired line with extreme accuracy, so as not to require painstaking care indisposing said strips on the sub-base,.thereby savin time as compared with the installation of ordinary division plates. The strips 8 are secured in place on the sub-base by means of stakes 9 driven into the sub-base, or other suitable means may be used for the purpose.

' The strips 8 have sockets 10 through which the stakes are driven. The strips 8 may be plain, so as to be cheap, and may even be composed of wood, fibre, paper and other materials.

The positioning of the strips 8 on the subbase is the first step of the method, and the next step consists in the pouring of the concrete on the sub-base between the rails 7 and over the strips. Said strips are placed on the sub-base in advance of the concrete mixer dividing the concrete at the bottom thereof.

The third step in the method consists in forming a groove or cut 12 in the s ace of the concrete above the strips 8. T is groove.

12 may be formed in the concrete while it is still plastic, and it is possible to make the groove follow a definite straight or curved line, so as to produce a neat and finished job. This groove not only provides a traffic line along the center of the road for dividing oppositely moving traffic, but also controls, in connection with the strips 8, the

breaking of the concrete after the concrete has set. The concrete will crack along the weakened portion between the strips 8 and groove 12, and even though the strips are not directly under the groove 12, the breaks will extend upwardly from said strips to the groove 12 due to the weakening of the con-- crete by said groove. As a result, the concrete will break accurately along the groove 12 although the breaks may be irregular below said groove. This irregular breaking of the concrete between the groove 12 and strips 8 is even of advantage in locking the adjacent edges of the opposite slabs or sections together againstrelative vertical displacement. cost and less expensive to install as compared with the division plates heretofore used, will provide for economy, and the groove 12 may be quickly formed in the surface of the concrete. It is also apparent that the strips 8 may be disposed transversely of the concrete with transverse grooves 12 above said strips, for producing transverse breaks or joints, and the strips and grooves may ex- -tend indifferent directions in various concrete surfacing structures for controlling breaks and producing joints.

The appliance shown in Figs. 1, 2 and 3 The strips 8 being cheaper in v for producing the groove 13 comprises a truck to move along one of the rails 7. Such truck is composed of a longitudinal beam 13 mounted near its ends on the wheels 14 adapted to roll on'the rail 7. Each wheel has an outer flange 15 to overlap the outer side of the rail, and disks 16 of sheet metal, preferably highly tempered steel, are bolted or otherwise secured to the inner sides ofthe wheels and have their edges formed to overlap the inner sides of the rail and to round off the corresponding outer corner of the concrete 11, as at 17. The wheels 14 will thus move along the rail, the flanges 15 and disks 16 holding said wheels in place on the rail, and the disks 16 will finish or round off the corresponding corner or edge ortion of the concrete as the device is move the. rail.

A bar 18 composed of channeliron or other suitable material extends across and is secured on the beam 13 between the wheels 14, and is connected to said beam by braces 19 and 19 Said bar 18 extends inwardly from the truck so as to move over the concrete, and carries the terminal. a

The trowel 20 comprises a top' piece 21 composed of sheet metal and disposed longitudinally of the road, said piece 21 being secured to the bar 18, and having its end portions bent back downwardly, as at 22. A bottom piece or shoe 23 is secured to the end portions 22 of the top piece 21 and is curved so as to present a convexed surface-to the concrete. The bottom resilient so as to be capa le' of being sprung toward a straight line position when pressed on the concrete, and'said shoe has a longitudinal rib 24 depending therefrom between its edges to produce the groove 12 in the surface of the concrete. The shoe 23 will smooth off the surface of the concrete at the opposite sides of the groove. The top piece grooving trowel 20 at its inner iece or shoe 23 is 21 is connected to the bar 18 by braces 25, and the trowel or tool 20 may be adjusted along the bar 18 to different position in order to space the groove 12 a desired distance from the corresponding side or edge ofthe road.

The bar 18 also projects outwardly a short distance beyond the beam 13, and an arch 26 is secured on the outer portion of said bar, and its inner limb is connected by braces 26 with the beam 13. Cross pieces 27 are secured on the arch 26 and handle rods 28 are secured to the pieces 27 at opposite sides of the arch 26 for conveniently moving the device along the road by hand in either direction. A suitable weight 29 is secured to the outer limb of the arch 26 in order to counterbalance the inner arm of the bar 18 and the trowel 20, so that the trowel 20 will not rest too heavily on the soft concrete when the hands are removed from the rods The grooving device is readily moved along the rail at one side of the road so as to produce an accurate groove which is parallel with the corresponding edge of the road. The pressure of the trowel on the concrete may be regulated by tilting the truck transv rsely on the rail, it being apparent that t e trowel may be raised and lowered by depressing and raising the handle rods 28, the wheels 14 tilting laterally on the rail.

Fig. 4 illustrates a modified construction of the. grooving device, which combines therewith a transverse bridge to extend across the concrete and support workmen. Thus, a transverse board or platform'18' extends across the road, and has one end secured on the beam 13' mounted on the wheels 14', and the opposite terminal of the latform is secured on short beams 30 carryin'g axles 31-on which wheels 32 are mounted.

The wheels 32 are similar to the wheels 14 to move on the opposite rail, and said Wheels 32 may be adjusted transversely on the axles. 31-for roads of different widths, or when negotiating curves in the road. The plat form 18' is braced against depression by the latticework 26, or other suitable stiffening structure. The wheels 32 need not be spaced apart so far as the wheels 14', inasmuch as the wheels 14' will avoid the tendency for the device to turn ofl the rails. A handle rod 28' is secured to the lattice work 26' 'above the beam 13 and extends beyond said connected, as at 33, to a support 34 fastened by a bolt 35 or otherwise to the platform 18',

trowel 20.

strip 8 above the ground.

said platform having a row of apertures 36 for adjusting the trowel 20' transversely for roads of different widths, although other adjustable supporting means for the trowel trowel. The spring 37 surrounds a rod 37 pivoted to the .top piece 21' and slidable through the arm 38, and said rod has a head at its upper end for the contactof the arm when the arm is raised, so as to raise the When the arm 38 is moved downwardly, the spring 37 is compressed with the desired pressure to press the trowel on the concrete with more or less pressure as desired. A hand lever 42 is secured to the rock shaft 39 at the side of the device where the beam 13 is located, in order that said' lever may be conveniently swung by the operator for raising and lowering the trowel. The lever 42 carries a dog 43 to engage a notched segment 44 carried by the beam 13' to maintain the trowel in its adjusted position.

With this device the trowel is raised and lowered by moving the lever 42, and the platform 18 may also support workmen in finishing the surface of the concrete either along the division line or between said line and the sides of the road.

Fig. 5 illustrates a division plate or strip 8 having a plate 50 riveted or otherwise secured to one side thereof at each end, and said plates have the depending sharpened o1 pointed portions 51 to enter the ground, thereby providing end stakes or pegs to enter the ground for holding the ends of the late or strip in position. In order to hol the the strip and has a hook 52 at its upper end to engage over the upper edge of the strip. Fig. 6 illustrates the use of a division plate or strip 8 which is of curved cross-section, and which is preferably supported above the ground or sub-base, so that when the concrete'sets it will crack between the upper edge of said strip and the groove 12, and between the lower edge of said strip and the ground or sub-base, thereby forming the opposite slabs or sections with an interlocking tongue and groove defined by the strip 8". In order to support the strip 8", the stake 9 which is driven into the ground may have an olfset or seat 53 to support'the strip, said strip having apertures through which the upper terminal of the stake passes.

Fig. 7 illustrates the stake 9 used with the strip 8 which is flat, for supporting the Having thus described the invention, What is claimed as new is I I 1. A concrete groovingdevice comprising a truck having wheels to move on a side rail defining the edge of a concrete road under construction, an inwardly extending bar mounted on said truck, said truck being adapted to be tilted transversely on the rail for raising and lowering said bar, a grooving tool carried by said bar, and a handle member connected to the truck and extending. outwardly therefrom for moving the truck on the rail and tilting the truck transversely.

2. A concrete grooving device comprising a truck having wheels to move on a side rail defining the edge of a concrete road under construction, an inwardly extending bar mounted on said truck, said truck being adapted to be tilted transversely on the rail for raising and lowering saidsbar, a grooving tool carried by said bar, and a Weight connected to the truck at the outer side thereof to counterbalance said bar and tool.

rsecuredto the truck to project inwardly and outwardly therefrom, a grooving tool carried by the inner arm of said bar, and a handle member and counterbalaneing weight mounted on the outer arm of said bar.

4, A concrete grooving trowel comprising a top piece and a curved resilient shoe secured at its ends to the top piece, said shoe having a wheel to move on one of said rails, and a disk secured to the 1nner side of said Wheel having its edge projecting beyond the periphery of said wheel to overlapsaid rail and having its edge portion formed to round off the corresponding edge of the concrete.

7 A concrete grooving device comprising a truck movable on the side rails defining the edges of a concrete road under construction, and a grooving tool carried by the truck having a shoe with a rounded surface to move on the concrete and provided with a longitudinal rib on the surface thereof to form a groove in the concrete.

8. A concrete grooving device comprising a truck having Wheels to move on a side rail defining the edge of a concrete road under construction, a grooving tool supported from said truck to move on plastic concrete, said truck being adapted to be tilted transversely on the rail for raising and lowering said tool. and a handle member carried by the truck for conveniently moving the truck on the siderail and tilting the truck.

In testimony whereof I hereunto alibi my signature.

JOSEPH WILLIAM HELTZEIJ. 

